title: [Studies on triterpenoids of Populus yunnanensis Dode].
abstract: Three triterpenoids (I, II and III) were isolated from the roots of Populus yunnanensis Dode, which has been used as a folk remedy for the treatment of urinary tract infection and calculus in Yunnan Province. Compound I and III were identified as friedelin and 21 alpha-hydroxyfriedelan-3-one and compound II as 21 alpha-acetoxyfriedelan-3-one which is a new triterpenoid. 13C NMR data of II showed that the presence of an alpha-acetoxy group at C-21 does not affect the boat conformation of ring E similar to the results in the study of some other D:A-friedo-oleananes.
authors.affiliation: Department of Chemistry, Shanghai Second Medical University.
authors.forename: Z N
authors.initials: ZN
authors.lastname: Chen
authors.forename: P J
authors.initials: PJ
authors.lastname: Xu
mesh_terms: D004365:Drugs, Chinese Herbal / Q000737:chemistry*; D008968:Molecular Conformation; D014197:Trees; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification*; D000094042:Lupanes
chemical_list: D004365:Drugs, Chinese Herbal; D014315:Triterpenes; C067162:21-hydroxyfriedelan-3-one; C067161:21-acetoxyfriedelan-3-one; C060796:friedelin; D000094042:Lupanes